Decomposition of Metham Sodium to Methylisothiocyanate as Affected by Wood Species, Temperature, and Moisture Content


  • Jeffrey J. Morrell


Fumigants, metham sodium, decomposition, wood chemistry, methylisothiocyanate


The effect of various wood characteristics on decomposition of metham sodium to methylisothio-cyanate in sixteen North American and Southeast Asian hardwoods and softwoods was investigated. While marked differences were noted in the degree of decomposition among some species, the relationship between decomposition and lignin content, extractive levels, wood pH, or 1% alkali solubility was slight within the various species. Wood moisture content had the greatest influence on decomposition, while temperature had a lesser effect. The results suggest that the wood environment could be manipulated to enhance metham sodium decomposition, thereby allowing dosage to be reduced or the period between applications to be prolonged.


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